Fourth Session

Make a move to make it move

من تحقرن المعروفالشيئا

بوجه أخاك تلقى أن لو وطليق.

. للناس عيش

Video

One & One

Design processes

1) Identify the need2) Background research3) Goal statement4) Performance specifications5) Ideation and invention

6) Analysis 7) Selection 8) Detailed design9) Prototyping and testing10) Production

Identify the need

• This step done for you by someone.•Brief and lacking in detail.

Background research

Don’t reinvent the wheel

Performance specifications

Define what it must do, not how it must do it.

Performance specifications Design specifications

Performance specifications

The enemy of design is the absence of specifications.

Ideation and invention

A. Idea generation.B. FrustrationC. IncubationD. Eureka !!

Let’s play

Ideation and invention

A. Idea generation.B. FrustrationC. IncubationD. Eureka !!

a) Idea generationBrainstorming• Quantity not Quality.• Superficial ridiculous ideas

are welcomed.• Ridicule is not allowed.

Analogies are useful when working alone.

slide

pull

jump

throw

move

b) Frustration

c) Incubation

Saturate yourself in the problem and background , relax! and let you subconscious do the hard work.

d) Eureka !!

If it didn’t happen , you have to do more ideation, redefinition or may be more research.

Analysis

Selection

Detailed design

CADmaterial chemicalelectricity .. etc

Prototypes and testing

Design processes

1) Identify the need2) Background research3) Goal statement4) Performance specifications5) Ideation and invention

6) Analysis 7) Selection 8) Detailed design9) Prototyping and testing10) Production

Production

Agenda

• Kinematics of Robotic arms with linear actuators:• Position analysis.• Velocity analysis.• Acceleration analysis.

• Kinetics of robotic arms with linear actuators:• Calculating motors torque.• Calculating cylinders pressure.

Actuators Classification according to the type of motion:• Rotary:• Electric motors (DC, Stepper, Servo.)• Hydraulic or Pneumatic rotary motors !!!

• Linear:• Electric solenoids.• Hydraulic cylinders.• Pneumatic Cylinders.

Span Constraint

Geometry

Reverse analysis

Adding linear actuators to the analysis

• Compressed length: S1, S2, S3.• Extension in cylinders: ΔS1, ΔS2, ΔS3.

Dynamic Analysis• Free Body Diagram.• Links Equations.• Governing Equations Matrix.• Links CG & Inertia.• Angular speed & Acceleration

Links Design Considerations

• Avoid Cantilever joints.• Account for radial load.• Less weight.• Grounding & Balancing.• Links rigidity.• Assembly & Disassembly.

Motor Driven Gripper

Practice